1. Field of the Invention
This invention relates to an aqueous dispersion for chemical mechanical polishing (CMP), to a polishing method and to a method for manufacturing a semiconductor device.
2. Description of the Related Art
In recent years, in concomitant with a trend to further increase the integration density of LSI, the wirings thereof are increasingly refined with the employment of Low-k insulating film and a high-conductivity material such as Cu. In the process of manufacturing semiconductor, steps such, in particular, a step for CMP such as a damascene wiring-forming step, a planarizing step and a washing step are considered key in promoting the refinement of the wirings.
In this CMP, it is required to perform the polishing with minimum damage to a polishing surface in order to prevent the peeling of film and the fracture of pattern, and hence it has been proposed to employ, as a slurry, an aqueous dispersion for CMP where resin particles are employed. There has been also proposed a slurry comprising an abrasive comprising inorganic particles having resin particles adsorbed on the surface thereof. In spite of these proposals, there is still an increasing demand to further enhance the polishing performance and the suppression of dishing. However, there is no technique known at present to sufficiently meet such a demand.